Summary

The selection of a respirator against bioaerosols can be a complex task, due to the lack of occupational exposure limits and toxicological data, as well as the limitations of the current sampling techniques and the wide variety of bioaerosols. Under these circumstances, a qualitative risk evaluation and management method provides an alternative to the quantitative methods used in occupational hygiene. This report proposes a control banding method for selecting respiratory protection against infectious and non-infectious bioaerosols applicable to all workplaces and intended for occupational hygienists and other occupational health and safety practitioners, as well as for experts who are members of learned societies. This model, which is follow-up to the Guide on Respiratory Protection against Bioaerosols , published by the Institut de recherche Robert-Sauvé en santé et en sécurité du travail (IRSST) in 2007, is based on bioaerosol-related knowledge and on approaches to control banding developed mainly for chemical contaminants and nanoparticles. The model is presented in the form of a matrix consisting of the four risk groups used in biosafety and of five exposure levels. The cross-tabulation of a risk group and a given exposure level corresponds to an assigned protection factor that allows the user to choose an appropriate respirator. The exposure level is itself the result of the sum of the scores assigned to the control levels and to the bioaerosol generation rates. Respiratory protection is therefore chosen on the basis of the danger represented by the bioaerosol, the workplace control level, and the type of activities carried out in the workplace. The model is simple to use and generally agrees with the opinions and recommendations of experts. This approach is in no way intended to replace the work of the occupational hygienist and should be used only by individuals with a sufficient level of knowledge and experience, in the context of an overall workplace risk assessment and management approach.